Merge tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs updates from Dave Chinner:
 "The major addition is the new iomap based block mapping
  infrastructure.  We've been kicking this about locally for years, but
  there are other filesystems want to use it too (e.g. gfs2).  Now it
  is fully working, reviewed and ready for merge and be used by other
  filesystems.

  There are a lot of other fixes and cleanups in the tree, but those are
  XFS internal things and none are of the scale or visibility of the
  iomap changes.  See below for details.

  I am likely to send another pull request next week - we're just about
  ready to merge some new functionality (on disk block->owner reverse
  mapping infrastructure), but that's a huge chunk of code (74 files
  changed, 7283 insertions(+), 1114 deletions(-)) so I'm keeping that
  separate to all the "normal" pull request changes so they don't get
  lost in the noise.

  Summary of changes in this update:
   - generic iomap based IO path infrastructure
   - generic iomap based fiemap implementation
   - xfs iomap based Io path implementation
   - buffer error handling fixes
   - tracking of in flight buffer IO for unmount serialisation
   - direct IO and DAX io path separation and simplification
   - shortform directory format definition changes for wider platform
     compatibility
   - various buffer cache fixes
   - cleanups in preparation for rmap merge
   - error injection cleanups and fixes
   - log item format buffer memory allocation restructuring to prevent
     rare OOM reclaim deadlocks
   - sparse inode chunks are now fully supported"

* tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (53 commits)
  xfs: remove EXPERIMENTAL tag from sparse inode feature
  xfs: bufferhead chains are invalid after end_page_writeback
  xfs: allocate log vector buffers outside CIL context lock
  libxfs: directory node splitting does not have an extra block
  xfs: remove dax code from object file when disabled
  xfs: skip dirty pages in ->releasepage()
  xfs: remove __arch_pack
  xfs: kill xfs_dir2_inou_t
  xfs: kill xfs_dir2_sf_off_t
  xfs: split direct I/O and DAX path
  xfs: direct calls in the direct I/O path
  xfs: stop using generic_file_read_iter for direct I/O
  xfs: split xfs_file_read_iter into buffered and direct I/O helpers
  xfs: remove s_maxbytes enforcement in xfs_file_read_iter
  xfs: kill ioflags
  xfs: don't pass ioflags around in the ioctl path
  xfs: track and serialize in-flight async buffers against unmount
  xfs: exclude never-released buffers from buftarg I/O accounting
  xfs: don't reset b_retries to 0 on every failure
  xfs: remove extraneous buffer flag changes
  ...

1 files changed, 29 insertions, 30 deletions

diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
index 097bf7717d80..0f1f165f4048 100644
--- a/fs/xfs/libxfs/xfs_da_btree.c
+++ b/fs/xfs/libxfs/xfs_da_btree.c
@@ -356,7 +356,6 @@ xfs_da3_split(
 	struct xfs_da_state_blk	*newblk;
 	struct xfs_da_state_blk	*addblk;
 	struct xfs_da_intnode	*node;
-	struct xfs_buf		*bp;
 	int			max;
 	int			action = 0;
 	int			error;
@@ -397,7 +396,9 @@ xfs_da3_split(
 				break;
 			}
 			/*
-			 * Entry wouldn't fit, split the leaf again.
+			 * Entry wouldn't fit, split the leaf again. The new
+			 * extrablk will be consumed by xfs_da3_node_split if
+			 * the node is split.
 			 */
 			state->extravalid = 1;
 			if (state->inleaf) {
@@ -446,6 +447,14 @@ xfs_da3_split(
 		return 0;
 
 	/*
+	 * xfs_da3_node_split() should have consumed any extra blocks we added
+	 * during a double leaf split in the attr fork. This is guaranteed as
+	 * we can't be here if the attr fork only has a single leaf block.
+	 */
+	ASSERT(state->extravalid == 0 ||
+	       state->path.blk[max].magic == XFS_DIR2_LEAFN_MAGIC);
+
+	/*
 	 * Split the root node.
 	 */
 	ASSERT(state->path.active == 0);
@@ -457,43 +466,33 @@ xfs_da3_split(
 	}
 
 	/*
-	 * Update pointers to the node which used to be block 0 and
-	 * just got bumped because of the addition of a new root node.
-	 * There might be three blocks involved if a double split occurred,
-	 * and the original block 0 could be at any position in the list.
+	 * Update pointers to the node which used to be block 0 and just got
+	 * bumped because of the addition of a new root node.  Note that the
+	 * original block 0 could be at any position in the list of blocks in
+	 * the tree.
 	 *
-	 * Note: the magic numbers and sibling pointers are in the same
-	 * physical place for both v2 and v3 headers (by design). Hence it
-	 * doesn't matter which version of the xfs_da_intnode structure we use
-	 * here as the result will be the same using either structure.
+	 * Note: the magic numbers and sibling pointers are in the same physical
+	 * place for both v2 and v3 headers (by design). Hence it doesn't matter
+	 * which version of the xfs_da_intnode structure we use here as the
+	 * result will be the same using either structure.
 	 */
 	node = oldblk->bp->b_addr;
 	if (node->hdr.info.forw) {
-		if (be32_to_cpu(node->hdr.info.forw) == addblk->blkno) {
-			bp = addblk->bp;
-		} else {
-			ASSERT(state->extravalid);
-			bp = state->extrablk.bp;
-		}
-		node = bp->b_addr;
+		ASSERT(be32_to_cpu(node->hdr.info.forw) == addblk->blkno);
+		node = addblk->bp->b_addr;
 		node->hdr.info.back = cpu_to_be32(oldblk->blkno);
-		xfs_trans_log_buf(state->args->trans, bp,
-		    XFS_DA_LOGRANGE(node, &node->hdr.info,
-		    sizeof(node->hdr.info)));
+		xfs_trans_log_buf(state->args->trans, addblk->bp,
+				  XFS_DA_LOGRANGE(node, &node->hdr.info,
+				  sizeof(node->hdr.info)));
 	}
 	node = oldblk->bp->b_addr;
 	if (node->hdr.info.back) {
-		if (be32_to_cpu(node->hdr.info.back) == addblk->blkno) {
-			bp = addblk->bp;
-		} else {
-			ASSERT(state->extravalid);
-			bp = state->extrablk.bp;
-		}
-		node = bp->b_addr;
+		ASSERT(be32_to_cpu(node->hdr.info.back) == addblk->blkno);
+		node = addblk->bp->b_addr;
 		node->hdr.info.forw = cpu_to_be32(oldblk->blkno);
-		xfs_trans_log_buf(state->args->trans, bp,
-		    XFS_DA_LOGRANGE(node, &node->hdr.info,
-		    sizeof(node->hdr.info)));
+		xfs_trans_log_buf(state->args->trans, addblk->bp,
+				  XFS_DA_LOGRANGE(node, &node->hdr.info,
+				  sizeof(node->hdr.info)));
 	}
 	addblk->bp = NULL;
 	return 0;